<!doctype html>
<body> <span></span> <script>
function boom() {
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  range.setEnd(document.body.childNodes[2], 0);
  window.addEventListener("DOMNodeInserted", f, true);
  function f() {
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    range.deleteContents();
  }
  range.deleteContents();
}
window.addEventListener("load", boom, false);
</script>
